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本文考察了Fe-Fe50wt.%Si扩散偶在1200C无磁场以及稳恒磁场下扩散层生长规律.利用真空浇注强制冷却技术制备Fe-Fe50wt.%Si扩散偶,将制备的扩散偶进行1200C不同磁感应强度下的热处理.对获得热处理后试样进行SEM与EDS线扫描分析,结果表明,无论无磁场还是稳恒磁场下Fe-Fe50wt.%Si扩散偶均生成两个扩散层,即FeSi相层和Fe-Si固溶体层,并且发现0.8T下的两个扩散层宽度均小于0T磁场下试样.按照抛物线规律,计算了扩散偶中间扩散层的互扩散系数,发现0.8T磁场下FeSi相层和Fe-Si固溶体层的互扩散系数较无磁场下分别降低了26.7%与34.1%.通过对磁吉布斯自由能的计算,发现0.8T磁场对扩散激活能Q的影响不足以影响扩散过程.但扩散过程中原子振动频率ν会受到磁场的影响,进而影响扩散常数D0,磁场对原子振动频率的影响可以用拉莫尔旋进理论进行解释.
In this paper, the growth of Fe-Fe50wt.% Si diffusion couple at 1200C without magnetic field and steady magnetic field was investigated. Fe-Fe50wt.% Si diffusion couple was prepared by vacuum casting forced cooling technique. Intensity heat treatment.The heat-treated samples were analyzed by SEM and EDS line scan results show that no magnetic field or steady magnetic field Fe-Fe50wt.% Si diffusion pairs are generated two diffusion layers, namely FeSi phase and Fe-Si solid solution layer, and found that the width of the two diffusion layers at 0.8T are smaller than the sample under 0T magnetic field.According to the parabolic law, the interdiffusion coefficient of diffusion intermediate diffusion layer is calculated and found that FeSi phase layer The interdiffusion coefficient of the Fe-Si solid solution layer is reduced by 26.7% and 34.1% respectively compared with the non-magnetic field. The calculation of the magnetic Gibbs free energy shows that the influence of the 0.8T magnetic field on the diffusion activation energy Q is not enough to affect the diffusion process. However, the atomic vibration frequency ν in the process of diffusion will be affected by the magnetic field, which will affect the diffusion constant D0. The influence of the magnetic field on the atomic vibration frequency can be explained by the Larmor’s screw-in theory.